The use of implantable access ports in the art of drug therapy is well known, in which an access port is implanted beneath the subcutaneous layers of a patient's skin. The known access ports are constructed to provide for repeated access to the vascular system of a patient, or a selected treatment site within the patient's body. The use of these devices reduces the trauma otherwise associated with multiple punctures of the skin, or the inconvenience of an externalized catheter for patient treatment purposes. For example, implantable access ports are used to facilitate frequent blood sampling, or to provide for the delivery of medications, nutritions, blood products, and imaging solutions into the patient's blood stream, or to a desired treatment site within the patient. Access to the implanted access port is typically accomplished by percutaneous needle insertion through the patient's skin into the access port through a penetrable septum or other similar structure by using a non-coring hypodermic needle.
Implantable access ports can also be used for apheresis, an extracorporeal procedure in which the blood of a donor or patient is passed through an apparatus that filters or separates out one or more components of the blood that contribute to a disease state and returns the remainder of the blood to the patient's blood circulation. Invasive apheresis treatments typically are administered frequently and can be painful as a result of the multiple venous punctures to the patient's skin. In order to most effectively perform apheresis procedures, the access ports should be capable of producing adequate blood flow rates and accommodating appropriately sized needles and catheters.
Implantable access ports are supplied as sterile devices, are generally provided for single patient use only, and can be available in a variety of port materials, including polysulfone, acetal plastic and titanium. Available catheter materials can comprise, without limitation, polyurethane and silicone. Suture holes are typically formed in the access port as a part of the base portion thereof and are used to facilitate the anchorage of the access port to the patient's underlying fascia, for example muscle. Implantable access ports are available in single, dual, and low profile models, and are available with attachable, or attached catheters. Implantable access ports are also currently available as power injectable ports for use in, for example, computed tomography (“CT”) scanning processes.
Dual model implantable access ports are comprised of two distinct fluid reservoirs contained within a single casing. These devices are useful when a health care provider needs to perform multiple functions that cannot be performed using a typical single reservoir model access port, for example to withdraw blood and administer medication via separate reservoirs. In conventional dual model access ports, each of the fluid reservoirs is circular in shape. This arrangement, however, leads to an increase in size of the geometric footprint of the access port because of the space created between the two circular reservoirs.
What is needed, therefore, is a dual model implantable access port that reduces the size of the geometric footprint of the access port, thereby reducing the size of incision necessary to implant the device in a patient, reducing patient discomfort and other potential medical complications. What is also needed is a dual reservoir implantable access port with a minimal geometric footprint that produces adequate blood flow rates for the performance of apheresis procedures, which can reduce trauma to patients and improve patient outcomes.